The scientific goal of this proposal is to investigate the effects of relative growth hormone deficiency and replacement on body composition and cardiovascular risk markers in men and women with abdominal obesity. The career development goal of this application is to support the candidate's professional development as a clinical investigator and successful mentor for fellows and junior faculty in patient-oriented clinical research by providing sufficient time for research and mentoring activities. The mentoring goal of this application is to facilitate the training of fellows and junior faculty in clinical research to form the basis of independent careers. The candidate's NHLBI-funded R01 grant investigating the effects of growth hormone replacement on body composition and cardiovascular risk markers in viscerally adipose men and women with relative growth hormone deficiency will form the basis for the training plan of the grant. Additional research opportunities are available in the form of ongoing studies that are funded by a number of other sources. The candidate has a record of leadership in mentoring on a national level and a successful track record of mentoring trainees in the Massachusetts General Hospital (MGH) Endocrine Fellowship program and other disciplines. The Institutional environment at the MGH, with a strong and diverse Medicine Department, Clinical Translational Science Center grant through Harvard Medical School, and Clinical Research Program, is outstanding. The Department of Medicine at the MGH has made a substantial commitment, including 90% protected time and dedicated space, toward the candidate's development as a clinical researcher responsible for training fellows and junior faculty. The Midcareer Investigator Award in Patient Oriented Research is an ideal mechanism to ensure the necessary support to reduce clinical and administrative responsibilities, and ensure the candidate's continued success as a mentor and clinical researcher. Project Narrative: Cardiovascular disease is the leading cause of death and illness in developed countries. This proposal investigates the role of low growth hormone levels as a possible hormone mechanism underlying the increased cardiovascular risk in women and men with abdominal adiposity and thus could have significant public health implications.